1. Field of the Invention
This invention relates to an optical arrangement of a camera for observing therethrough an object to be photographed, and more particularly to a viewfinder optical arrangement for taking out part of a picture-taking light beam from within the optical path of a picture-taking lens and confirming therethrough the picture-taking field of view by this light beam, and especially an optical arrangement suitable for a video camera or a cinecamera.
2. Description of the Prior Art
An ordinary video camera, as shown in FIG. 1 of the accompanying drawings, generally forms an image on an image pick-up tube 15 with the aid of a picture-taking lens comprising a forward lens group or unit 11 and a rearward lens group or unit 12. A TTL viewfinder is designed such that part of a picture-taking light beam is reflected by a beam splitter such as a half-transmitting prism 10 provided in the optical path between the forward lens group 11 and the rearward lens group 12, an inverted image is formed on a focus screen 4 by a viewfinder master lens 2 via a reflecting mirror 3, an erect image is formed on another focus screen 6 by a relay lens 5 and the erect image on the focus screen 6 is observed by the observer's eye E through an eyepiece 7. The fact that such a relay lens is required has led to a very great length of the optical path of the viewfinder optical arrangement, and this has been disadvantageous to making the entire camera compact.